Aerodynamic mud flap

ABSTRACT

Embodiments include a mud flap having a barrier section configured to intercept and deflect matter discharged from the tire when rotating during vehicle operation. The barrier section including a plurality of horizontal louvers, each horizontal louver forming an elongate member having a length extending primarily in a direction of the mud flap width, where the plurality of horizontal louvers are spaced apart in the direction of the mud flap height in the form of an array, where the plurality of horizontal louvers are configured to intercept and deflect matter of a minimum size traveling along any linear trajectory path from the outer circumference of the tire/wheel assembly towards the front side of the mud flap while substantially maximizing the spacing between adjacent louvers to minimize aerodynamic drag. Other embodiments provide a method of using the mud flap.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 16/652,015, filed Mar. 27, 2020 with the U.S. Patent Office,and claims priority to, and the benefit of, U.S. patent application Ser.No. 16/652,015, filed Mar. 27, 2020 with the U.S. Patent Office,International patent application no. PCT/US2018/053761, filed Oct. 1,2018 with the U.S. Patent Office (as a Receiving Office), andInternational patent application no. PCT/US2017/054514, filed Sep. 29,2017 with the U.S. Patent Office (as a Receiving Office), where eachsuch prior patent application is hereby incorporated by reference.

BACKGROUND Field

Embodiments of this disclosure relate generally to mud flaps for use onwheeled vehicles, such as trucks, semi tractors and trailers.

Description of the Related Art

Mud flaps are employed to form a barrier into which matter thrownrearward from a rotating tire is cast to protect any trailing vehicle.Due to the importance of improving fuel consumption to reduceoperational costs, there is a need to provide mud flaps that improveaerodynamic performance, such as by reducing or minimizing aerodynamicdrag, without notably reducing the capability of the mud flap to operateas a barrier.

SUMMARY

Embodiments of the disclosure include a mud flap for a vehicle andmethods of using a mud flap.

In particular embodiments, the mud flap is configured for installationin a mounted position on a vehicle adjacent a tire/wheel assembly tointercept and deflect matter being projected by the tire/wheel assemblyfrom an outer circumference of the tire/wheel assembly and along any ofa plurality of linear trajectory paths tangent to the outercircumference of the tire when the tire/wheel assembly is in rotationduring vehicle operation and to permit the passage of air flow throughthe mud flap during vehicle operation to prevent the generation ofelevated aerodynamic drag. The mud flap includes a height, a width, anda thickness, where in the mounted position the height extends primarilyin a vertical direction, the width extending perpendicular to theheight, the thickness of the mud flap being defined by a front side anda rear side of the mud flap, the front side facing the tire/wheelassembly and configured to engage the matter being projected by therotating tire/wheel assembly and the rear side forming an outlet for thepassage of air flow through the mud flap. The mud flap includes abarrier section configured to intercept and deflect matter projectedfrom an outer circumference of the tire when rotating during vehicleoperation, the barrier section including a plurality of horizontallouvers, each horizontal louver forming an elongate member having alength extending primarily in a direction of the mud flap width, wherethe plurality of horizontal louvers are spaced apart in the direction ofthe mud flap height in the form of an array, the spacing betweenadjacent to horizontal louvers within the plurality of horizontallouvers increasing with increasing height of the mud flap. Eachhorizontal louver has a width and a thickness, the horizontal louverwidth extending perpendicular to the horizontal louver thickness andbeing greater than the horizontal louver thickness, both the horizontallouver width and the horizontal louver thickness extending perpendicularto a horizontal louver length, where a centerline of the horizontallouver thickness extends longitudinally at an inclination angle relativeto a direction of the mud flap thickness, such that a bottom of thehorizontal louver partially faces downward and partially faces the frontside of the mud flap. The plurality of horizontal louvers are configuredto intercept and deflect matter of a minimum size traveling along anylinear trajectory path from the outer circumference of the tire/wheelassembly towards the front side of the mud flap while substantiallymaximizing the spacing between adjacent louvers to minimize aerodynamicdrag.

In particular embodiments a method of using a mud flap on a vehiclehaving a tire/wheel assembly includes providing a mud flap in a mountedposition on the vehicle adjacent to the tire/wheel assembly, the mudflap configured to intercept and deflect matter being projected by thetire/wheel assembly from an outer circumference of the tire/wheelassembly and along any of a plurality of linear trajectory paths tangentto the outer circumference of the tire when the tire/wheel assembly isin rotation during vehicle operation and to permit the passage of airflow through the mud flap during vehicle operation to prevent thegeneration of elevated aerodynamic drag. It is appreciated that the mudflap may form any mud flap contemplated herein, including the mud flapdescribed in the preceding paragraph, for example.

The foregoing and other objects, features, and advantages will beapparent from the following more detailed descriptions of particularembodiments, as illustrated in the accompanying drawings wherein likereference numbers represent like parts of particular embodiments.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a mud flap in accordance with one embodimentof the disclosure;

FIG. 2 is a elevational side sectional view of elongated members takenalong line 2-2 in FIG. 1 within an aerodynamic section of the mud flap;

FIG. 3A is a elevational side sectional view of horizontal louvers takenalong line 3A-3A in FIG. 1;

FIG. 3B is a elevational side sectional view of horizontal louvers takenalong line 3B-3B in FIG. 1;

FIG. 4 is a elevational side sectional view of a vertical arrangement ofhorizontal louvers taken along line 4-4 in FIG. 1, showing aprogressively increasing spacing between louvers with increasing heightalong the mud flap;

FIG. 5 is a side elevational view of a rotating tire and the sectionalview of the vertical arrangement of horizontal louvers shown in FIG. 4,showing the trajectory of matter being thrown rearward from a forwardrotating tire; and,

FIG. 6 is an expanded side view of FIG. 5, also showing a bottom of atrailer.

FIG. 7 is a diagram showing downward air flow through the array ofhorizontal louvers shown in FIG. 4.

FIG. 8 is a side elevational view of a rotating tire and a sectionalview of a plurality of horizontal louvers arranged in an array in avertical arrangement;

FIG. 9 is an enlarged view of FIG. 8 at location 9, showing adjacenthorizontal louvers with points of intersection along exterior surfaces(respective front and rear exterior surfaces) of adjacent louversaligned along a trajectory line;

FIG. 10 is a side elevational view showing adjacent horizontal louversin an alternative arrangement to those shown in FIG. 9, where points ofintersection along exterior surfaces (respective corresponding leadingand trailing edges) of the adjacent horizontal louvers are spaced apartrelative to a trajectory line to provide a spaced opening configured topermit certain matter to pass within the spaced opening while operatingas a barrier to intercept and deflect matter larger than the spacedopening;

FIG. 11 is a side elevational view showing adjacent horizontal louversin an alternative arrangement to those shown in FIGS. 9 and 10, wherepoints of intersection along exterior surfaces (respective correspondingleading and trailing edges) are spaced apart relative to a trajectoryline to provide a permissible overlap of the adjacent horizontallouvers;

FIG. 12 is a side elevational view of a rotating tire and a sectionalview of a plurality of horizontal louvers arranged in an array in avertical arrangement where the inclination angle of the louversdecreases with increased positional elevation along the mud flap height;

FIG. 13 is a side elevational view similar to FIG. 9 showing adjacenthorizontal louvers with points of intersection along exterior surfaces(respective leading and trailing edges) aligned along a trajectory linein accordance with another embodiment;

FIG. 14 is a chart showing a non-linear relationship between increasingadjacent louver spacing and increasing vertical location along a mudflap height; and,

FIG. 15 is a chart showing a non-linear relationship between increasingadjacent louver spacing and increasing linear trajectory path angle froma rotating tire of a tire/wheel assembly.

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

This disclosure describes aerodynamic mud flaps for use wheeledvehicles. To improve aerodynamic performance, such as by the reductionor minimization of aerodynamic drag, openings are formed in the mud flapto allow airflow to pass through the mud flap during vehicle movementwhile still preventing the passage of certain matter through mud flap.In certain instances, these openings can be described as forming thespacing between adjacent elongated members referred to herein ashorizontal louvers. Without making certain alterations, simply providingopenings in the mud flap creates an opportunity for matter thrownrearward from a forward rotating tire to pass through any such opening,reducing the effectiveness of the mud flap to operate as a barrier.Therefore, the mud flap may be further adapted to better operate as abarrier, where both aerodynamic and barrier capabilities are generallymaximized.

An improved mud flap can be described as having a height, a width, and athickness. In an intended mounted arrangement on a vehicle, the heightextends primarily in a vertical direction, the width extendingperpendicular to the height, and the thickness extending perpendicularto both the height and the width. The thickness can be described asbeing less than each of the height and width, and in particularinstances, substantially less than each of the height and width. The mudflap thickness extends from a front side to a back side of the mud flap.

Optionally, in particular instances, the mud flap includes a mountingsection. The mounting section is configured to facilitate mounting ofthe mud flap to a vehicle and adjacent to a tire, such as may be mountedon a wheel to form a tire/wheel assembly. It is appreciated that themounting section may be located anywhere on the mud flap, but commonly,it is located at or near the top of the mud flap, where the top of themud flap connotes the maximum height of the mud flap in an elevationalsense. The mounting section may include any desired mechanism tofacilitate attachment of the mud flap to a vehicle. For example, incertain instances, the mounting section includes a first set of mountingfeatures, configured to facilitate attachment of the mud flap to amounting structure on the vehicle, such as by way of a first set ofmounting orifices configured to receive a fastening member, such as abolt or screw, for example. Any such mounting feature may form a recessor aperture to facilitate attachment of the mud flap to the vehicle. Anaperture may be configured to receive some fastening member. A recessforms an indentation, such as to indicate where an aperture may beformed for mounting purposes, such as when the recesses represent apre-existing pattern for mounting the mud flap to a particular set ofmounting orifices on the vehicle.

The mud flap further includes a barrier section. The barrier section isconfigured to intercept and deflect matter discharged from a rotatingtire during vehicle operation. Such matter may be any matter that may befound on a ground surface, such as road debris, stones, and water (whichmay take the form of water spray). When a mounting section is present,the mounting section and the barrier section may be arranged atdifferent heights along the mud flap height. In certain instances, thebarrier section is located below the mounting section, in relation tothe mud flap height. In other words, the mounting section and thebarrier section are arranged at different heights along the mud flapheight, except that there may be overlap between the sections along theheight.

In certain instances, the barrier section can be described as having aplurality of elongate openings extending primarily in the direction ofthe mud flap width (that is, primarily in a widthwise direction of themud flap). Primarily in a direction of the mud flap width means adirection biased less than 45 degrees relative to the direction of themud flap width. Adjacent elongate openings within the plurality ofelongate openings are spaced apart by a particular distance, such as tobalance the need to maximize the spacing to provide increased air flowthrough the mud flap against the need to minimize the spacing to preventthe passage of certain matter projected from a tire. Therefore, due tothe trajectory of matter being expelled from the tire at differentlocations about the outer periphery of an annular tire tread (the tiretread forming an outer annular periphery around the tire), whether suchtrajectory is linear or arcuate, to balance air flow through the mudflap while also maintaining desired barrier capabilities, narrowerelongate openings are provided at lower elevations along the mud flapwhile greater elongate openings are provided at higher elevations alongthe mud flap.

In particular instances, the barrier section includes a plurality ofhorizontal louvers, each horizontal louver forming an elongate memberhaving a length extending primarily in a direction of the mud flapwidth. Primarily in a direction of the mud flap width means a directionbiased less than 45 degrees relative to the direction of the mud flapwidth. The plurality of horizontal louvers are spaced apart in thedirection of the mud flap height in the form of an array. These spacingsrepresent an exemplary embodiment of the elongate openings moregenerally discussed in the prior paragraph, as elongate openings may beprovided without the need for horizontal louvers. While the horizontallouvers are spaced apart to promote improved aerodynamic performance,the horizontal louvers are also oriented and arranged to eliminate anysee-through opening for any matter to pass or to instead provide someamount of permissible see-though opening representing a maximumsee-through opening to prevent matter sized greater than the see-throughopening to pass between the adjacent horizontal louvers when directedrearward along a trajectory path from a forward rotating tire, that is,as a vehicle is traveling in a forward direction. For design purposes,this trajectory path may be linear (straight-line) or non-linear orarcuate. It has been determined that due to the close spacing between amud flap and a tire for which the mud flap offers protection, for anyanticipated over the road rotational speed of the tire, a lineartrajectory is a good approximation for the trajectory of matterextending from the tire and to the mud flap, as in many instances alinear or slightly arcuate trajectory is provided within the range ofanticipated rotational speeds (when vehicle is traveling 10 to 65 milesper hour and when spacing between tire and mud flap is 4 to 10 inches).In instances where the trajectory path is linear, the trajectory pathforms a line tangent to the outer surface of the tire tread in adirection of forward tire rotation. In instances where the trajectorypath is non-linear, while the trajectory may initially extend in adirection tangent to the tire tread, the path may decrease elevationallyto form a slightly arcuate path. Any of these trajectories may beemployed for mud flap design purposes, taking into account the type ofmatter, its size, and weight, as well as any range of rotational tirespeeds.

Because the angle at which matter traveling along these trajectory pathsare low when engaging lower portions of the mud flap and higher whenengaging higher portions of the mud flap, greater spacings betweenadjacent horizontal louvers is acceptable at higher locations along themud flap. Accordingly, in certain instances, the spacing betweenadjacent horizontal louvers within the array increases as the positionof each horizontal louver in the array is arranged higher along the mudflap height away from a bottom and towards a top of the mud flap. Moregenerally, it can also be stated that, on average, the spacing increaseswith increasing horizontal louver location along the mud flap height forall horizontal louvers arranged within the barrier section, whichaccounts for minor deviations from the generally increasing spacingarise within the array. While any desired spacings may be employed, incertain exemplary instances, the spacing between adjacent horizontallouvers varies from 0.1 to 0.5 inches, from the bottom to the top of thearray. In more specific instances, the spacing between adjacenthorizontal louvers varies from 0.1 and 0.2 inches at the bottom of thearray to 0.35 to 0.5 inches at the top of the array. These spacingdimensions identified are measured in the direction of the mud flapheight, or, stated differently, in a direction normal to the directionof the mud flap thickness (the direction of minimum mud flap thickness).

In addition to this increased spacing between adjacent horizontallouvers, horizontal louvers are arranged biased to the direction of themud flap thickness, or, described differently, biased relative tohorizontal, for the purpose of directing the bottom of each horizontallouver partially towards a front side of the mud flap, as well asdirectionally closer to being normal to a target trajectory path alongwhich matter travels rearward from the forward rotating tire, where thefront side of the mud flap is intended to face a rear side of a tiremounted on a vehicle. In doing so, it follows that each horizontallouver within the array can be described as having a width and athickness, the width being greater than the thickness and extendingperpendicular to the thickness. Both the width and the thickness extendperpendicular to the horizontal louver length, where the width extendsat an angle (also referred to as an inclination angle herein) relativeto the direction of the mud flap thickness or to horizontal (that is, adirection parallel to the ground plane), where the angle is greater thanzero degrees and in particular instances less than 90 degrees. In otherwords, the width extends partially in a direction of the mud flap heightand partially in a direction of the mud flap thickness. The use of suchangled or biased horizontal louvers provides additional benefits overthe benefits attained when increasing elongate openings (spacings) withincreasing elevational location along the mud flap height.

In certain instances, when arranging adjacent horizontal louvers closerdue to a reduced spacing and/or when increasing the inclination angle bywhich the width is biased to the direction of the mud flap thickness, afront, or front edge, of a first horizontal louver is arrangedelevationally higher than a rear, or rear edge, of a second horizontallouver, the second horizontal louver being arranged adjacent to andelevationally above the first horizontal louver. The front edge is alsoreferred to herein as a leading edge, while the rear edge is alsoreferred to herein as a trailing edge. In such arrangements, each of thefront and front edge is arranged along a front half of the horizontallouver associated with a front half of the louver width while each ofthe rear and rear edge is arranged along a rear half of the horizontallouver associated with a rear half of the louver width. The front halfis arranged closest to a front side of the mud flap while the rear halfis arranged closest to the rear side of the mud flap. In combination,the inclination angle by which the widthwise direction of eachhorizontal louver is biased relative to the mud flap thickness or tohorizontal (that is, a horizontal plane), and the spacing betweenadjacent horizontal louvers within the plurality of louvers in thebarrier section are each selected such that the plurality of horizontallouvers (the array) eliminates or minimizes any see-through openingthrough which matter (having a width) traveling along a straight-linetrajectory rearward from a forward-rotating tire would otherwise pass,the straight-line trajectory being tangent to an outer surface of thetire tread (that is, an outer radial surface associated with an outercircumference of the tire tread). It is appreciated that an outersurface or outer circumference of the tread may form a portion of theouter, ground-contacting outer surface of the tread or any voidextending into the tread thickness from the outer, ground-contactingouter surface. A void may form any desired void, such as any groove orsipe. However, when eliminating the see-through along the lineartrajectory path, over-correcting by creating a notable overlap betweenadjacent horizontal louvers will reduce aerodynamic performance byincreasing aerodynamic drag with a reduction in frontal see-through.Frontal see-through refers to the straight-line see-through extending inthe direction of the mud flap thickness from the front side to the rearside of the mud flap, as opposed to straight-line see-through asobserved along a linear trajectory path extending from an outercircumference of the tire. In other words, see-through relative to alinear trajectory path extending substantially tangent to an outercircumference of a tire is measured in the directions perpendicular tothis path, while frontal see-through is measured in the directionsperpendicular to the direction of the mud flap thickness, which, whenmounted on a vehicle, is a horizontal direction.

In furtherance of this purpose, it is appreciated that the inclinationangle by which the width of each adjacent horizontal louver extendsrelative to the direction of the mud flap thickness or to horizontalwill depend on the width of the horizontal louvers, the spacing betweenadjacent louvers, and the distance by which the mud flap is intended tobe installed from the tire. In certain embodiments introduced below,equations are introduced below that create an association of theseparameters. In certain instances, the inclination angle of eachhorizontal louver of the plurality of horizontal louvers issubstantially the same. In other instances, the inclination angledecreases with increasing mud flap height. In other words, theinclination angle by which the width is biased increases the higher ahorizontal louver is located along the height of the mud flap. Thisreduces the aerodynamic drag at higher elevations along the mud flapwhere horizontal louvers are more horizontal as they are biased lessrelative to horizontal with a lower inclination angle. This lowerinclination angle is achievable due to the linear trajectory path alongwhich matter is cast tangent from a radially outer surface along thecircumference of the tire. For a lower trajectory path, where thetrajectory path intersects the mud flap elevationally at a lowerlocation along the mud flap height, a greater inclination angle isdesired in these embodiments to reduce see-through along the trajectorypath. As a result, the greater inclination angle permits greater spacingbetween horizontal louvers. For a higher trajectory path, where thetrajectory path intersects the mud flap elevationally at a higherlocation along the mud flap height, a lower inclination angle is desiredin these embodiments to reduce see-through along the trajectory path. Asa result, the greater inclination angle permits greater spacing betweenhorizontal louvers. In these embodiments, for the plurality ofhorizontal louvers, the widths of the horizontal louvers and the spacingbetween the horizontal louvers may vary or remain the same.

With regard to spacing, generally, the lower a horizontal louver islocated along the mud flap, the closer the straight-line trajectory ofmatter thrown from the tire is to horizontal (that is, parallel to aground plane). Therefore, in instances when the inclination angle bywhich the width of each adjacent horizontal louver extends is the same,for purposes of blocking passage of any matter travelling along atrajectory path through the space between adjacent horizontal louvers(that is, reducing see-through along the path), the closer a horizontallouver is to the bottom of the mud flap, the closer the spacing betweenadjacent horizontal louvers and/or the greater the width of eachadjacent horizontal louver. By way of example, in certain instances,where the width of each horizontal louver in the plurality of horizontallouvers is substantially the same (constant) and the inclination angleby which each such horizontal louver is inclined relative to horizontalis substantially the same (constant), the width is 0.25 to 1 inch, or inmore particular instances, substantially 0.375 inches, and theinclination angle is an angle ranging from 0 to 50 degrees, or in moreparticular instances from 15 to 45 degrees or an angle of substantially30 degrees. In such instances, the mud flap may be installed aparticular distance between the mud flap and the tire, such as distancefrom 4 to 10 inches, or, in more particular instances, from 6 inches to8 inches. Also, in such instances, the spacing between adjacenthorizontal louvers varies from 0.1 and 0.2 inches at the bottom of thearray to 0.35 to 0.50 inches at the top of the array. These mud flapsmay be used on any wheeled vehicle. For example, these mud flaps may beused on over-the-road vehicles, such as tractors and trailers, whichemploy tires having inflated diameters generally ranging from 0.25meters (m) to 1.25 m.

With regard to the size of the spacing between adjacent horizontallouvers, it is appreciated that certain matter may be permitted to passthrough each spacing (passage), as it has been observed that due to theair flowing through the spacing and due to the general downwarddirection of the passage formed by way of the spacing between adjacenthorizontal louvers, such matter will be directed downwardly towards aground surface. This downward direction is better provided when thespacing between adjacent horizontal louvers is closer (lower on the mudflap). It is noted that the air flow is not only directed downwardly byway of the downwardly directed passage, the air flow is characterized ashaving increased speeds resulting in lower air pressures. Therefore, bydownwardly angling the passaged formed by the spacing between adjacenthorizontal louvers on the back side of the mud flap, passage of matteris directed downwardly to provide additional barrier capabilities.

As it is appreciated that the spacing, inclination angle, and width areall dependent on one another to effectively block any straight-linetrajectory from entering the spacing between adjacent horizontal louversalong the height of the mud flap, in certain instances, the inclinationangle may be altered between adjacent horizontal louvers to prevent(block) the straight-line trajectory from entering the spacing betweenthe adjacent horizontal louvers. In particular exemplary instances, theinclination angle by which the width extends for each horizontal louverof the plurality of horizontal louvers decreases with increasingvertical position within the array in the direction of the mud flapheight, which may or may not be combined with increased spacing betweenadjacent horizontal louvers and/or altering the widths of the horizontallouvers with increasing vertical positioning of the horizontal louversalong the mud flap height. In altering the widths, in certain instances,the width of each horizontal louver increases with increasing verticalposition within the array in the direction of the mud flap height.

It is appreciated that strengthening members may extend between adjacenthorizontal louvers to provide structural integrity and durability. Thesestrengthening members may extend in any direction desired. For example,in particular instances, a plurality of elongate strengthening membersextend primarily in the vertical direction, that is, in the direction ofthe mud flap height, across the plurality of horizontal louvers, whereeach elongate strengthening member of the plurality of elongatestrengthening members extends between two or more horizontal louvers ofthe plurality of louvers. These vertical strengthening members may ormay not be combined with other strengthening members in any desiredarrangement. For example, in certain instances the plurality of elongatestrengthening members are arranged in a honeycomb arrangement.

Optionally, in addition to the herein described barrier section, anaerodynamic section may also be included elevationally above the barriersection, although it is appreciated that an aerodynamic section asdescribed herein may be incorporated into a traditional mud flap, wherethe barrier section may or may not include any openings extendingthrough its thickness. The aim of the aerodynamic section is to minimizefrontal area (surface or cross-sectional area) that impedes air flow byproviding as much void (opening/spacing) for air to flow through duringvehicle operation so to provide improved aerodynamic mud flapperformance. In instances when a mounting section is provided, themounting section may be arranged at any location suitable for itsintended purpose. In certain instances, for example, it is arrangedabove the aerodynamic section.

The aerodynamic section includes a plurality of elongate members, withadjacent elongate members within the plurality being spaced apart by adesired distance. In certain instances, the amount of frontalsee-through spacing is greater than the frontal see-through spacing ofthe barrier section. More narrowly, it can be said that an averagefrontal see-through spacing between adjacent elongate members in theaerodynamic section is greater than an average frontal see-throughspacing between adjacent horizontal louvers in the barrier section. Thisincrease in frontal see-through spacing may be achieved by increasingthe spacing between adjacent elongate members and/or by altering aninclination angle by which the widthwise extension (the width) of eachelongate member is biased relative to a forward direction (that is, thedirection of the mud flap thickness). For example, in certain instances,the spacing between adjacent elongate members within the aerodynamicsection are greater than the spacing between adjacent horizontal louversin the barrier section. In certain instances, the spacing adjacentelongate members within the aerodynamic section is 0.5 inches orgreater, and in more specific instances, 0.5 to 0.7 inches. Thesespacing dimensions identified are measured in the direction of the mudflap height, or, stated differently, in a direction normal to thedirection of the mud flap thickness (the direction of minimum mud flapthickness).

It is appreciated that each elongate member of the plurality of elongatemembers in the aerodynamic section has a width and a thickness, thewidth of each elongate member extending perpendicular to the thicknessof the elongate member and being greater than the thickness of theelongate member. Both the width and the thickness extend perpendicularto a length of the elongate member. The width extends at an inclinationangle relative to a direction of the mud flap thickness. In certaininstances, this inclination angle is zero, such that the width extendsin a direction normal to the front side of the mud flap. In suchinstances, the spacing between adjacent elongate members is more fullyexposed, unlike the spacing between horizontal louvers in the barriersection, which are arranged to prevent the passing of certain matterthrough the spacing between adjacent horizontal louvers. In otherinstances, the inclination angle may be minimized, such as ranging from10 to −10 degrees or to substantially zero (0) degrees. In yet otherinstances, if knowing the direction of the air flowing into theaerodynamic section, the inclination angle may be altered such that thewidth extends in a substantially parallel with a particular direction ofair flow to more fully expose the spacing between adjacent elongatemembers to the air flow.

It is appreciated that each elongate member in the aerodynamic sectionmay be arranged in any manner desired suitable for the intended purposeof the aerodynamic section. In particular, it is appreciated that alength of the elongate member may extend lengthwise in any desireddirection. For example, in certain instances, the length of eachelongate member of the plurality of elongate members extends primarilyin the vertical direction of the mud flap, that is, in the direction ofthe mud flap height, where adjacent elongate members within theplurality of elongate members are spaced apart in a direction of the mudflap width. By extending primarily in the vertical direction, thebending stiffness in the aerodynamic section is increased, which isbeneficial for better resisting the propensity for the mud flap to bendin this area arranged elevationally above the barrier section and closeto the mounting section. This is due to the bending moment created byimpacts and aerodynamic forces occurring at lower parts of the mud flapwithin the barrier section. The mud flap is effectively a cantileveredstructure, where the mounting section forms a base of the cantileveredstructure about which portions of the mud flap may bend and rotate. Itfollows that the further a force is applied along the cantileveredstructured (that is, along the mud flap) from the base, a greaterbending moment is generated acting about the base. Therefore, for thisreason, the mud flap will observe higher bending forces along the mudflap, such as at locations nearest the mounting section, due to forcesbeing applied closer to its bottom further from the mounting section.For these reasons, adapting the aerodynamic section to provide increasedbending resistance by way of an increased bending modulus would providea mud flap that would better remain in a downwardly extended orientationduring vehicle operation.

As with the barrier section, the aerodynamic section may includestrengthening members extending across adjacent elongate members. Incertain instances, these strengthening members may be elongate in formso to minimize any impact on aerodynamic performance, and may bearranged in any manner contemplated for the plurality of elongatemembers, except that the strengthening members must be arranged tointersect adjacent elongate members. For example, in certain instances aplurality of elongate strengthening members extend across the pluralityof elongate members in the aerodynamic section, where each elongatestrengthening member of the plurality of elongate strengthening membersin the aerodynamic section extends between two or more elongate membersof the plurality of elongate members. In more particular instances, byexample, the plurality of elongate strengthening members in theaerodynamic section forms a honeycomb arrangement. Additionalstrengthening members may also be employed in the aerodynamic section asmay be needed to maintain structural integrity and durability.

Further embodiments of this disclosure include methods of using any mudflap described herein on a vehicle adjacent a tire/wheel assembly.

For example, in certain instances, a method of using a mud flap on avehicle having a tire/wheel assembly includes providing a mud flap in amounted position on the vehicle adjacent to the tire/wheel assembly. Themud flap is configured to intercept and deflect matter being projectedby the tire/wheel assembly from an outer circumference of the tire/wheelassembly and along any of a plurality of linear trajectory paths tangentto the outer circumference of the tire when the tire/wheel assembly isin rotation during vehicle operation. The mud flap is also configured topermit the passage of air flow through the mud flap during vehicleoperation to prevent the generation of elevated aerodynamic drag. Themud flap has a height, a width, and a thickness, such as has previouslybeen described herein. The mud flap thickness can be described as beingdefined by a front side and a rear side of the mud flap, the front sidefacing the tire/wheel assembly and configured to engage the matter beingprojected by the rotating tire/wheel assembly. The rear side also formsan outlet for the passage of air flow through the mud flap in itsentirety. It certain instances, the mud flap thickness is defined by apair of parallel planes each forming one of the front and rear sides ofthe mud flap. The mud flap also includes a barrier section configured tointercept and deflect matter projected from an outer circumference ofthe tire when rotating during vehicle operation. The barrier sectionincludes a plurality of horizontal louvers, such as has been generallydescribed herein, where the horizontal louvers have a length extendingprimarily in a direction of the mud flap width. The spacing betweenadjacent horizontal louvers within the plurality of horizontal louversincreases with increasing height of the mud flap, that is, as theplurality of horizontal louvers are arranged positionally higher inelevation within the array and along the mud flap height. Eachhorizontal louver has a width and a thickness as generally describedherein, such that a centerline of the horizontal louver thicknessextends longitudinally at an inclination angle relative to a directionof the mud flap thickness or to a horizontal plane, such that a bottomof the horizontal louver partially faces downward and partially facesthe front side of the mud flap. This centerline generally extends in thedirection of the mud flap with. This inclination angle may range from of0 to 50 degrees, by way of example, or by any other range disclosedherein. In particular embodiments, for each horizontal louver arrangedpositionally higher in elevation within the array, the angle by whichthe centerline of the horizontal louver thickness is oriented relativeto the mud flap thickness remains substantially constant with increasingheight of the mud flap in certain instances, or, in other embodiments,may decrease with increasing height. It is appreciated that the arraymay or may not include all horizontal louvers arranged within the mudflap, as certain adjacent horizontal louvers may substantially be of thesame size, shape, and orientation. In any event, the plurality ofhorizontal louvers are configured to intercept and deflect mattergreater than a minimum size traveling along any linear trajectory pathfrom the outer circumference of the tire/wheel assembly towards thefront side of the mud flap while substantially maximizing the spacingbetween adjacent louvers to minimize aerodynamic drag.

In certain instances, where for the matter to be projected from thetire/wheel assembly along a linear trajectory path towards the frontface of the mud flap in the mounted position, adjacent horizontallouvers for the plurality of horizontal louvers are arranged such that aline tangent to the outer circumference of the tire/wheel assembly (thetangent line representing one possible linear trajectory path) firstintersects an exterior surface of a first horizontal louver of adjacenthorizontal louvers, such as at longitudinal centerline of the firsthorizontal louver thickness, and thereafter intersects a longitudinalcenterline of a thickness of a second horizontal louver arrangedadjacent to and elevationally higher than the first horizontal louver.In such arrangements where the line intersects an exterior surface ofthe first horizontal louver, the line can be said to intersect a frontor front half of the first horizontal louver, such as a front edgeassociated with a front half of the louver width, for example. As notedpreviously, a front or front half is arranged closest to a front side ofthe mud flap while a rear or rear half is arranged closest to the rearside of the mud flap. In these instances, when intersecting the firsthorizontal louver, the line intersects the exterior surface withoutextending into the thickness of the first horizontal louver, such aswhen the line is tangent to the exterior surface, for example. Along thelongitudinal centerline of the second horizontal louver thickness, thetangent trajectory line either intersects an exterior surface of thesecond horizontal louver, is spaced apart from the second horizontallouver, or intersects the second horizontal louver. In such arrangementswhere the line intersects an exterior surface of the second horizontallouver, it can be said that the line intersects a rear or rear half ofthe second horizontal louver, such as a rear edge associated with a rearhalf of the louver width, for example. In these instances, whenintersecting the second horizontal louver, the line intersects theexterior surface without extending into the thickness of the secondhorizontal louver, such as when the line is tangent to the exteriorsurface, for example. In particular instances, in being spaced apartfrom the aligned arrangement (where the trajectory line would intersectthe exterior surface or trailing edge of the second horizontal louverwithout extending into the second horizontal louver thickness), thetangent trajectory line is located up to 3.81 mm (0.15 inches) from thealigned arrangement and the trailing edge of the second horizontallouver in a direction perpendicular to the line. In particular instancesthe thickness of each horizontal louver is substantially the same foreach louver within the plurality of louvers, but each may vary asdesired in other instances. Optionally, the thickness of each horizontallouver may vary along the width of the horizontal louver, such as whenforming an airfoil, for example. Other mud flap variations as discussedherein may be employed in any of these embodiments. For example, inparticular instances, the width of each horizontal louver is 0.25 to 1inch, or in more particular instances, substantially 0.375 inches, andthe inclination angle by which the widthwise extension of eachhorizontal louver is biased relative to a horizontal plane ranges from 0to 50 degrees, or in more particular instances from 15 to 45 degrees oran angle of substantially 30 degrees. In such instances, the mud flapmay be installed a particular distance between the mud flap and thetire, such as distance from 4 to 10 inches, or, in more particularinstances, from 6 inches to 8 inches. Also, in these instances, thespacing between adjacent horizontal louvers varies from 0.1 and 0.2inches at the bottom of the array to 0.35 to 0.45 inches at the top ofthe array.

Certain exemplary embodiments are discussed below in association withthe figures.

With reference to FIG. 1, a mud flap in accordance with an exemplaryembodiment is shown. In particular, the mud flap 10 has a height H₁₀, awidth W₁₀, and a thickness t₁₀ (see FIG. 4, as not shown in FIG. 1, butnote the thickness extends into the page perpendicular to both theheight H₁₀ and width W₁₀). The thickness t₁₀ can be described as beingless than each of the height H₁₀ and width W₁₀, and in particularinstances, substantially less than each of the height H₁₀ and width W₁₀.With reference to FIG. 4, the mud flap thickness t₁₀ extends from afront side F₁₀ to a rear side R₁₀ of mud flap 10.

In the embodiment shown in FIG. 1, mud flap 10 includes a mountingsection 20, a barrier section 30, and an aerodynamic section 40. Barriersection 30 and aerodynamic section 40 and are each located belowmounting section 20, while aerodynamic section 40 is located betweenmounting section 20 and barrier section 30, all in relation to mud flapheight H₁₀. It can also be said that mounting section 20, having heightH₂₀, barrier section 30, having height H₃₀, and aerodynamic section 40,having height H₄₀, are each arranged at different heights H₂₀, H₃₀, H₄₀along height H₁₀ of mud flap 10. Mud flap height H₁₀ extends between mudflap bottom Bio and mud flap top T₁₀, where “above” and “higher”indicate an elevational direction or bias towards top T₁₀, while “below”and “lower” indicate an elevational direction or bias towards bottomBio. Mounting section 20 is located near top T₁₀ of mud flap 10, wheretop T₁₀ defines the maximum height of mud flap 10 in an elevationalsense opposite bottom Bio. It is appreciated that mounting section 20 isconfigured to facilitate mounting of mud flap 10 to a vehicle.Aerodynamic section 40 is configured to maximize airflow through mudflap 10, while barrier section 30 is configured to permit air flowthrough mud flap 10 while also being configured to intercept and deflectmatter discharged rearward from a forward rotating tire during vehicleoperation, such as, for example, road debris, stones, and water.

With continued reference to FIG. 1, mounting section 20 includesmounting features 22, configured to facilitate attachment of the mudflap to a mounting structure on a vehicle, where any mounting featuremay form a recess or aperture. When a mounting section is included inany mud flap contemplated herein, it is appreciated that any mountingsection may be employed, where such mounting section may employ the useof any known desired features, if at all, to facilitate installation ofthe mud flap onto a vehicle.

With continued reference to FIG. 1, barrier section 30 includes aplurality of horizontal louvers 32, each horizontal louver 32 forming anelongate member having a length L₃₂ extending primarily in a directionof mud flap width W₁₀. Primarily in a direction of the mud flap widthW₁₀ means a direction biased less than 45 degrees relative to thedirection of mud flap width W₁₀. In barrier section 30, the plurality ofhorizontal louvers 32 are spaced apart in the direction of mud flapheight H₁₀ in the form of an array. This can also be observed in FIG. 4,showing in cross-section a plurality of horizontal louvers arrangedwithin an array A₃₂ from FIG. 1. The spacing between adjacent horizontallouvers 32 is identified as S₃₂.

With continued reference to FIG. 1, while horizontal louvers 32 arespaced apart to promote improved aerodynamic performance, horizontallouvers 32 are also oriented and arranged to prevent any notablesee-through (opening) for any desired matter travelling along astraight-line, rearward trajectory path that has been rotationallythrown from a forward-rotating tire. This straight-line trajectory pathP, with reference now to FIGS. 5 and 6, forms a line tangent to theouter surface of tire 50 of a tire/wheel assembly in a direction of tirerotation R. With additional reference to FIG. 4, the spacing S₃₂ betweenadjacent horizontal louvers 32 within the array A₃₂ increases as theelevational position of each horizontal louver 32 within the array isarranged higher along mud flap height H₁₀ and barrier section heightH₃₀. Spacings S₃₂ also represent elongate openings and passages. This ismost clearly shown when comparing the spacing S₃₂ between adjacenthorizontal louvers 32 shown in FIGS. 3A and 3B, where in FIG. 3Aadjacent horizontal louvers 32 are arranged closer to mud flap bottomBio and therefore are spaced closer together than horizontal louvers 32shown in FIG. 3B, which are arranged closer to mud flap top T₁₀ thanhorizontal louvers 32 of FIG. 3A. It can be stated that the averagespacing S₃₂ increases with increasing horizontal louver location alongheight H₁₀ of mud flap 10 for all horizontal louvers 32 arranged withinbarrier section 30, which accounts for minor deviations from thegenerally increasing spacing arise within the array A₃₂. For example, incertain variations, the spacing S₃₂ between adjacent horizontal louvers32 approximately forming the bottom 10% and approximately the top 10% ofhorizontal louvers 32 shown in barrier section 30 are spaced equally,while the plurality of horizontal louvers arranged between theapproximately bottom 10% and top 10% are arranged with increased spacingS₃₂ as the horizontal louvers 32 are positionally arranged closer to topT₁₀. This is because more narrowly spacing the approximately bottom 10%of horizontal louvers 32 would not have been reasonably effective andbecause more widely spacing the approximately top 10% of horizontallouvers 32 would have risked compromising the mud flap structuralintegrity without adding additional strengthening members or makingother design changes. Also, more widely spacing the approximately top10% of horizontal louvers 32 may have exceeded a maximum spacing foreffective barrier functionality.

With reference to FIGS. 4 and 5, in addition to providing increasedspacing S₃₂ between adjacent horizontal louvers 32 with increasedelevation within the array, horizontal louvers 32 are oriented in abiased arrangement relative to the direction of the mud flap thicknesst₁₀, or, described differently, biased relative to horizontal, byinclination angle α for the purpose of directing the bottom B₃₂ of eachhorizontal louver 32 directionally closer to being normal to a lineartrajectory path P and/or arcuate trajectory path P′ of matter that maybe thrown rearward from the forward-rotating tire 50, where inclinationangle α is greater than zero degrees. Thereby, any see-through openingis eliminated between adjacent horizontal louvers 32 that otherwisewould be sufficient for matter to pass when traveling along trajectorypath P.

To describe this biased orientation more specifically, with specificreference to FIGS. 3A and 3B, each horizontal louver 32 within the arraycan be described as having a width W₃₂ and a thickness t₃₂, the widthW₃₂ being greater than the thickness t₃₂ and extending perpendicular tothe thickness t₃₂. Both the width W₃₂ and the thickness t₃₂ extendperpendicular to the horizontal louver length L₃₂ (see FIG. 1), wherethe width W₃₂ extends at an inclination angle α relative to thedirection of the mud flap thickness t₁₀ or, more generally, relative tohorizontal (that is, a direction or plane parallel to the ground plane).Stated differently, width W₃₂ extends partially in a direction of themud flap height H₁₀ and partially in a direction of the mud flapthickness t₁₀. By doing so, a bottom B₃₂ (bottom side) of horizontallouver 32 partially faces a front side F₁₀ of mud flap 10, where frontside F₁₀ of mud flap 10 is intended to face a rear side of tire 50 toeliminate any see-through opening that otherwise would allow matter topass between the adjacent horizontal louvers 32 along trajectory path P.In other variations, adjacent horizontal louvers 32 are arranged withsome permissible see-though opening representing a maximum see-throughopening to prevent matter sized greater than the see-through opening topass between the adjacent horizontal louvers 32 along trajectory path P.It is appreciated that while trajectory path P is linear in theembodiment shown, an arcuate trajectory path P′ (shown as dashed line inFIG. 5) may be employed when configuring the spacing of adjacenthorizontal louvers 32. In any event, in any embodiment contemplated,with reference to FIG. 7, any matter permitted to pass through a spacingS₃₂ between adjacent horizontal louvers 32 may be directed downwardlytowards a ground surface due to the downwardly directed passage (at itsdownstream exist from the back side of the mud flap) formed by spacingS₃₂ between adjacent horizontal louvers 32 as the matter passes throughspacing S₃₂ and the corresponding downward direction of air flowing 70through spacing S₃₂. It is noted that as spacings S₃₂ become narrower atlower elevations of the mud flap, the downward direction by which airflow travels upon exiting the mud flap increases. It is further notedthat while inclination angle α may change between adjacent horizontallouvers 32, in the exemplary embodiment shown, inclination angle αremains constant between adjacent horizontal louvers 32 throughout thearray A₃₂ of horizontal louvers 32. These results were also achievedusing a barrier section comprised of horizontal louvers arranged in thevarious embodiments described in association with Eqns. 1 and 2 below,and as otherwise described herein.

With reference to FIG. 3A, due to the inclination angle α by which thewidthwise extension of each horizontal louver 32 is biased relative tothe direction of the mud flap thickness t₃₂ and due to the closerspacing S₃₂ needed at lower locations along barrier section 30 to blockmatter cast along trajectory path P (see FIG. 4) from passing betweenadjacent horizontal louvers 32, a front edge FE₃₂ (a leading edge), ormore generally a front, of a first horizontal louver 32 is arrangedelevationally higher than a rear edge RE₃₂ (a trailing edge), or moregenerally a rear, of a second horizontal louver 32, as is represented byoverlap O₃₂. This may not always occur, such as when the spacing S₃₂between adjacent horizontal louvers 32 increases with increasingelevational position along mud flap height H₃₂, such as is shown byexample in FIG. 3B. Each of the front and front edge FE₃₂ is arrangedalong a front half of the horizontal louver associated with a front halfof the louver width W₃₂ while each of the rear and rear edge RE₃₂ isarranged along a rear half of the horizontal louver width W₃₂. The fronthalf is arranged closest to a front side F₁₀ of the mud flap 10 whilethe rear half is arranged closest to the rear side R₁₀ of the mud flap10.

With reference to FIGS. 4 and 5, it is appreciated that each of theinclination angle α by which the horizontal louver width W₃₂ is biasedrelative to the direction of the mud flap thickness t₁₀ and the spacingS₃₂ by which adjacent horizontal louvers 32 are spaced, as is sufficientto prevent matter from passing between adjacent horizontal louvers 32along a linear trajectory path P, and/or arcuate trajectory path P′, maychange depending upon the distance de separating tire 50 and mud flap 10in its installed position (as intended). As noted herein, theinclination angle α for each horizontal louver 32 and its width W₃₂ mayremain substantially constant or vary between louvers 32 within theplurality of horizontal louvers. By way of example, the plurality ofhorizontal louvers 32 shown in FIGS. 3A-11 show a horizontal louvers 32having widths biased relative to horizontal by an inclination angle α,which is substantially the same (that is, equal or constant) betweenadjacent louvers 32, and for all louvers 32, within the plurality oflouvers 32. By further example, with reference to FIG. 12, variation ininclination angle α is shown within the plurality of horizontal louvers32, where the inclination angle α changes between adjacent louvers 32.In this instance, the inclination for each louver 32 decreases withincreasing elevational position along the mud flap height H₁₀. It isappreciated that the spacing between adjacent louvers may vary or mayremain the same within the array or more generally within the pluralityof louvers. It is noted that in other instances, inclination angle α maynot change between each pair of adjacent louvers within a plurality ofhorizontal louvers 32. For example, while the trend may be forinclination angles α to decrease (or increase) with increasedelevational position along the mud flap height H₁₀, there may beadjacent louvers within an array of louvers 32 where the inclinationangle α does not substantially change (that is, remains constant). It isnoted that inclination angles α may be measured along a linearcenterline CL₃₂ of the louver thickness, such as is shown in FIGS. 3A-11or along an average linear centerline CL ₃₂ as exemplarily shown in FIG.13. FIG. 13 shows horizontal louvers having asymmetrical thicknesses,such that the centerline of each thickness centerline extends along anon-linear path. A linear average centerline CL ₃₂ may be obtained bygenerating a linear curve fit for the non-linear centerline CL₃₂, suchas by performing a linear regression of the non-linear centerline CL₃₂.It is from this linear average centerline CL ₃₂ an inclination angle maybe measured relative to horizontal (that is, in a direction of the mudflap thickness or in a direction perpendicular to the mud flap height).

With reference again to FIG. 1, barrier section 30 includes a pluralityof elongate strengthening members 34 extending between adjacenthorizontal louvers 32 to provide structural integrity and durability tobarrier section 30 and mud flap 10. These elongate strengthening members34 extend primarily in the vertical direction, that is, in the directionof the mud flap height H₁₀, where each elongate strengthening member 34of the plurality of elongate strengthening members extends between twoor more horizontal louvers 32. These vertical strengthening members mayor may not be combined with other strengthening members in any desiredarrangement. While elongate strengthening members 34 could extend thesubstantial height H₃₀ of barrier section, in the example shown,additional elongate strengthening members 36 are provided to form ahoneycomb arrangement of elongate strengthening members in combinationwith elongate strengthening members 34. Additional strengthening membersmay also be employed in the barrier section as may be needed to maintainstructural integrity and durability, such as strengthening members 38,which extend across the width of the barrier section and at a biasthereto, and which form the shape of a chevron or “V”.

With continued reference to the exemplary embodiment shown in FIG. 1, anaerodynamic section 40 is arranged above barrier section 30. Aerodynamicsection 40 provides a reduced frontal area (that is, surface area orcross-sectional area) to increase air flow through mud flap 10, as it islocated above barrier section 30 at a elevational location that does notrequire this portion of the mud flap 10 to operate as a barrier. This isbecause in such instances, with reference to FIG. 6, any matterextending along straight-line trajectory path P from tire 50 at theheight of aerodynamic section 40 would, if passing through aerodynamicsection 40, impact a bottom B₆₀ of vehicle 60, which in this embodimentis a trailer. Still, to provide a barrier for larger, more damagingobjects, such as large stones, debris, or the like, and to also providestructural integrity for mud flap 10 as may be needed, aerodynamicsection 40 as shown in FIG. 1 includes a plurality of elongate members42, where adjacent elongate members 42 within the plurality of elongatemembers are spaced apart by a desired distance.

With reference to FIG. 1, as well as the cross-sectional view of certainelongate members 42 in FIG. 2, it is appreciated that each elongatemember 42 in aerodynamic section 40 has a width W₄₂ and a thickness t₄₂,the width W₄₂ of each elongate member extending perpendicular to thethickness t₄₂ of the elongate member 42 and being greater than thethickness t₄₂ of the elongate member. Both the width W₄₂ and thethickness t₄₂ extend perpendicular to elongate member length L₄₂ (seeFIG. 1). Width W₄₂ extends in the direction of the mud flap thicknesst₁₀ (or, in other words, in a direction substantially normal to thefront side F₁₀ of mud flap 10), such that the direction of width W₄₂ issubstantially aligned in parallel with a direction normal N to mud flapfront side F₁₀. By doing so, the spacing S₄₂ between adjacent elongatemembers 42 in aerodynamic section 40 is more fully exposed to air flowdirected normal to the mud flap front side F₁₀, unlike the spacing S₃₂between horizontal louvers 32 in barrier section 30 (see FIGS. 3A and3B), which are arranged to prevent the passing of certain matter alongtrajectory path P through the spacing S₃₂ between adjacent horizontallouvers 32. It is appreciated that, if knowing the direction of the airflowing into the aerodynamic section, the elongate members may betwisted (biased or angled) so to more fully expose the spacing betweenadjacent elongate members to the particular air flow. Accordingly, inother variations, width W₄₂ may extend at a bias (at an angle (3 otherthan zero degrees) relative to the direction of mud flap thickness t₁₀.While each elongate member 42 in aerodynamic section 40 may be arrangedin any manner desired, in the exemplary embodiment shown in FIG. 1, thelength L₄₂ of each elongate member 42 extends lengthwise primarily inthe vertical direction of mud flap 10, that is, in the direction of themud flap height H₁₀, where adjacent elongate members 42 are spaced apartin the direction of the mud flap width W₁₀.

With reference to the exemplary embodiment shown in FIG. 2, the spacingS₄₂ between adjacent elongate members 42 in aerodynamic section 40 isshown in greater detail, where spacing S₄₂ also represents a frontalsee-through spacing S₄₂ ^(F). As can be observed, with additionalreference to FIGS. 3A and 3B, the amount of frontal see-through spacing(opening) S₄₂ provided in the aerodynamic section 40 is, on average (byarea), greater than the frontal see-through spacing (opening) S₃₂F ofbarrier section 30. This increase in frontal see-through spacing betweenaerodynamic section 40 and barrier section 30 may be achieved byproviding a lower angle by which the widthwise extension W₄₂ of any suchelongate member in aerodynamic section 40 extends relative to thedirection of the mud flap thickness t₁₀, or, stated differently,relative to a direction N normal to the front side F₁₀ of the mud flap(which can be described as a plane extending in the direction of the mudflap height H₁₀ and in the direction of the mud flap width W₁₀).Additionally or separately, the increase in frontal see-through spacingin aerodynamic section 40 relative to barrier section 30 may be achievedby simply providing a greater spacing S₄₂ between adjacent elongatemembers 42 that is greater than spacing S₃₂ between adjacent horizontallouvers 32.

As with barrier section 30, with continued reference to FIG. 1,aerodynamic section 40 includes strengthening members 44, which in theaerodynamic section 40 extend across adjacent elongate members 42.Strengthening members 44 are elongate in form so to minimize any impacton aerodynamic performance. While strengthening members 44 may bearranged in any manner desired, provided each at least extends acrossadjacent elongate members, in the exemplary embodiment shown, aplurality of elongate strengthening members 44 extend primarily in adirection of the mud flap width W₁₀. More specifically, a plurality ofelongate strengthening members 44 are arranged in aerodynamic section 40to form a honeycomb arrangement. Additional strengthening members mayalso be employed in the aerodynamic section as may be needed to maintainstructural integrity and durability.

With reference to FIG. 8, a rotating tire (or tire/wheel assembly) 50 isshown projecting matter along linear trajectory paths P in the directionof rotation R towards a front side F₁₀ of the mud flap 10. Each lineartrajectory path P extends from an outer circumference OC₅₀ of the tireor tire/wheel assembly 50 and is tangent to said outer circumferenceOC₅₀. The outer circumference OC₅₀ of the tire/wheel assembly is definedby radius r. The ground plane is denoted as GP. Each linear trajectorypath P is oriented by an angle φ relative to the ground plane GP or moregenerally relative to a horizontal plane HP. Mud flap 10 has a heightH₁₀, a thickness t₁₀, and is mounted a particular distance from thetire, which can be described using distance L, which extendshorizontally in a direction parallel to the ground plane GP or in adirection of the vehicle length Lv from a rotational axis A of thetire/wheel assembly 50 and to the rear side R₁₀ of the mud flapthickness t₁₀. It is noted that the spacing of adjacent louvers 32within the barrier section increases with increasing vertical locationalong the mud flap height H₁₀. It is noted that the inclination angle(a) of each horizontal louver 32 (see FIGS. 9-11), which biases thewidth (widthwise extension) of a corresponding horizontal louver 32relative to a horizontal or ground plane, remains constant amongst alllouvers in the array. In this instance, with the front side F₁₀ and backside R₁₀ forming parallel planes, the width W₃₂ of each horizontallouver 32 remains constant, but may optionally vary between louvers 32,such as when increasing with increasing vertical location along the mudflap height H.

With reference to FIG. 9, which shows an enlarged portion of FIG. 8,adjacent horizontal louvers 32 within the barrier section are shownarranged such that the a point of intersection along an exterior surfaceof a front or leading edge FE₃₂ of a first horizontal louver 32 ₁ (thatis, an elevationally lower louver) is aligned with a point ofintersection along exterior surface the trailing edge RE₃₂ of a secondhorizontal louver 32 ₂ (that is, an elevationally higher louver) of theadjacent louvers along a linear trajectory path P, where neither pointof intersection extends into the thickness of the corresponding louver.In doing so, the linear trajectory path P extends along a portion of theexterior surface associated with a front or front edge FE₃₂ of the firsthorizontal louver 32 ₁ and along a portion of the exterior surfaceassociated with a rear or rear edge RE₃₂ of the second horizontal louver32 ₂. Extending along a portion of the exterior surface associated witha front or front edge FE₃₂ may occur at an intersection of the thicknesscenterline CL₃₂ along a corresponding front edge FE₃₂ or at any otherlocation along the front edge FE₃₂ or more generally along the fronthalf of the louver width W₃₂ along the exterior surface of the louver.Likewise, extending along a portion of the exterior surface associatedwith a rear or rear edge RE₃₂ may occur at an intersection of thethickness centerline CL₃₂ along a corresponding rear edge RE₃₂ or at anyother location along the rear edge FE₃₂ or more generally along the rearhalf of the louver width W₃₂ along the exterior surface of the louver.In FIGS. 3A-12, the front edges FE₃₂ and rear edges RE₃₂ are rounded andextend until reaching a top or bottom side of each corresponding louver.In other variations, any front or rear edge may be generally flat orplanar or be pointed. In FIG. 13, the front edge FE₃₂ is rounded, andthe rear edge RE₃₂ is generally pointed.

With reference again to FIG. 9, linear trajectory path P of matterprojected from a rotating tire is inclined by an angle φ relative to ahorizontal plane HP. Each horizontal louver width W₃₂ is biased by angleα relative to a horizontal plane HP, while Y is the vertical componentof louver width W₃₂ and X is the horizontal component of louver widthW₃₂.

In particular embodiments, a desired arrangement between adjacenthorizontal louvers can be determined using particular equations. Use ofthese equations permits one to determine a proper spacing betweenadjacent horizontal louvers to provide improved aerodynamic performancewhile also providing sufficient barrier capabilities.

In certain instances, to determine the vertical spacing of adjacenthorizontal louvers within a barrier section of a mud flap, Eqn. 1 isprovided below, whereby the spacing of adjacent horizontal louvers andthe inclination angle (α) of each horizontal louver width increases withincreasing vertical location along the mud flap height. F represents thedistance by which adjacent horizontal louvers are spaced in the verticaldirection such that the leading edge or point of intersection with anexterior surface along a front of a first horizontal louver is alignedwith the trailing edge or point of intersection with an exterior surfacealong a rear of a second horizontal louver along one possible lineartrajectory paths for matter projected from a rotating tire, such as isgenerally shown in FIG. 8, where the line along which alignment isarranged does not extend into the thickness of the corresponding louver.A first horizontal louver for a pair of adjacent louvers is the one oflowest elevation, such that it is the first louver of the pairapproached along a linear trajectory path. It is also noted that inspacing apart adjacent horizontal louvers, vertical spacing Fspecifically extends between longitudinal centerlines of eachcorresponding louver width. Y represents a distance corresponding to thevertical component of louver width W₃₂, while X represents a distancecorresponding to the horizontal component of louver width W₃₂. φrepresents the angle by which linear trajectory path P is orientedrelative to ground plane GP or to a horizontal plane HP.

F=Y+X·tan φ  (Eqn. 1)

In utilizing Eqn. 1, with reference to FIG. 9, F includes two additivecomponents, namely, Y and X·tan φ. In Eqn. 1, Y represents distance F₁and the vertical height associated with first louver width W₃₂, whileX·tan φ represents distance F₂ and the vertical distance extendingbetween the leading edge FE₃₂ or point of intersection with an exteriorsurface along a front of the first louver 32 ₁ and the trailing edgeRE₃₂ or point of intersection with an exterior surface along a rear ofthe second louver 32 ₂ along trajectory path P. In sum, F is the sum ofF₁ and F₂, which forms the distance extending from the first louvertrailing edge RE₃₂ to the second louver 32 ₂ trailing edge RE₂. Again,Eqn. 1 determines the location of a second, adjacent horizontal louverrelative a first, adjacent horizontal louver to align the leading edgeor point of intersection with an exterior surface along a front of thefirst louver with the trailing edge or point of intersection with anexterior surface along a rear of the second louver along a common linerepresenting a possible linear trajectory path of matter from a rotatingtire. This arrangement balances the compromise between aerodynamic andbarrier performances.

A deviation from the aligned arrangement provided by Eqn. 1 may beachieved using Eqn. 2, provided below. Eqn. 2 provides a spacing (oroffset) from the linear trajectory path use to align respective leadingand trailing edges, or front and rear, of the first and second adjacentlouvers. This is achieved by adding or subtracting a vertical spacing oroffset component S·sec φ, S being the distance of offset desired in adirection perpendicular to the linear trajectory path used in Eqn. 1 toalign the respective leading and trailing edges of adjacent louvers.

F=Y+·tan φ±S·sec φ  (Eqn. 2)

For example, with reference to FIG. 10, a positive spacing S has beenadded, separating respective leading and trailing edges, or front andrear, of first and second adjacent louvers. This results in an increasein vertical spacing F beyond distances F₁ and F₂ as found in Eqn. 1 byS·sec φ, which is referred to as distance F_(S+). This positive spacingS improves aerodynamic performance while permitting smaller,unconcerning matter equal to or less than spacing S to pass through themud flap and between adjacent louvers along a linear trajectory path. Byfurther example, with reference to FIG. 11, a negative spacing S hasbeen added, which reduces the vertical distance F by S·sec φ, which isreferred to as distance F_(S−), to create an overlapped arrangementbetween the first and second adjacent louvers relative to the lineartrajectory path P. While this overlapped arrangement may reduceaerodynamic performance due to the smaller spacing between adjacentlouvers, the overlapped arrangement may prevent the passage of matterthrough the mud flap that otherwise would pass through the mud flap inthe aligned arrangement. Also, the overlapped configuration may improvethe barrier function of the mud flap to better intercept mattertraveling along an arcuate trajectory path. Further, the overlappedarrangement may better deflect matter downward as it passes through themud flap. It is noted that spacing S is different from the spacing S₃₂described above in association with FIGS. 3A-4.

In particular embodiments, to balance the benefits and sacrifices toaerodynamic and barrier performances, S is in the range of ±0.15 inchesor ±3.81 mm. Optionally, the width W₃₂ of each horizontal louver is 0.25to 1 inch, or in more particular instances, substantially 0.375 inches,and the angle α by which the widthwise extension W₃₂ of each horizontallouver is biased relative to a horizontal plane HP ranges from 0 to 50degrees, or in more particular instances from 15 to 45 degrees or anangle of substantially 30 degrees. In such instances, the mud flap maybe installed a particular distance between the mud flap and the tire,such as distance from 4 to 10 inches, or, in more particular instances,from 6 inches to 8 inches. Also, in these instances, the spacing Fbetween adjacent horizontal louvers varies from 0.1 and 0.2 inches atthe bottom of the array to 0.35 to 0.45 inches at the top of the array.Surprisingly, when incorporating these design features into a mud flap,the water spray and mist were directed substantially downward,noticeable improving visibility for trailing vehicles.

In an effort to determine the height HL at which a first louver 32 ₁ ofa pair of adjacent louvers is located relative to a particular lineartrajectory path P, Eqn. 3 is provided, where: r is the radius of thetire or tire/wheel assembly; L is horizontal distance from thetire/wheel assembly rotational axis A to the rear side of the mud flap;and φ is the angle by which linear trajectory path P is orientedrelative to ground plane GP or horizontal plane HP. In operation, theheight HL of an intersection between trajectory path P and the rear sideR₁₀ of the mud flap 10 is shown in FIG. 8, together with the additivecomponents H₁ and H₂ for determining HL, where H₁ equals (r−r·cos φ) andwhere H₂ equals (L−r·sin φ)·tan φ.

HL=[(r−r·cos φ)+(L−r·sin φ)·tan φ]  (Eqn. 3)

In evaluating the relationship between adjacent louver spacing F asprovided by Eqns. 1 and 2 and the corresponding height HL of trajectorypath P associated with each pair of aligned, adjacent horizontallouvers, it has been learned that the relationship is non-linear, as thespacing F increases at a higher rate relative to trajectory height HL.This is evidenced by the graph shown in FIG. 14, where F_(min)corresponds to F_(S−) and F_(max) corresponds to F_(S+). This is alsotrue when evaluating the relationship between louver spacing F asprovided by Eqns. 1 and 2 and the corresponding angle φ of trajectorypath P associated with each pair of aligned, adjacent horizontallouvers. This is evidenced by the graph shown in FIG. 15, where F_(min)corresponds to F_(S−) and F_(max) corresponds to F_(S+). Therefore, itcan be said in these certain embodiments that the spacing F betweenadjacent horizontal louvers increases non-linearly and at a greater ratewith increasing vertical location along the mud flap height. In othervariations, a linear increase may be observed using different louverarrangements.

It is appreciated that any mud flap discussed herein may be installed onany contemplated vehicle adjacent to a tire, the tire being rotatablymounted to the vehicle for vehicle operation. In doing so, duringvehicle operation, the mud flap performs as described herein.

To the extent used, the terms “comprising,” “including,” and “having,”or any variation thereof, as used in the claims and/or specificationherein, shall be considered as indicating an open group that may includeother elements not specified. The terms “a,” “an,” and the singularforms of words shall be taken to include the plural form of the samewords, such that the terms mean that one or more of something isprovided. The terms “at least one” and “one or more” are usedinterchangeably. The term “single” shall be used to indicate that oneand only one of something is intended. Similarly, other specific integervalues, such as “two,” are used when a specific number of things isintended. The terms “preferably,” “preferred,” “prefer,” “optionally,”“may,” and similar terms are used to indicate that an item, condition orstep being referred to is an optional (i.e., not required) feature ofthe embodiments. Ranges that are described as being “between a and b”are inclusive of the values for “a” and “b” unless otherwise specified.

While various improvements have been described herein with reference toparticular embodiments thereof, it shall be understood that suchdescription is by way of illustration only and should not be construedas limiting the scope of any claimed invention. Accordingly, the scopeand content of any claimed invention is to be defined only by the termsof the following claims, in the present form or as amended duringprosecution or pursued in any continuation application. Furthermore, itis understood that the features of any specific embodiment discussedherein may be combined with one or more features of any one or moreembodiments otherwise discussed or contemplated herein unless otherwisestated.

What is claimed is:
 1. A mud flap configured for installation in amounted position on a vehicle adjacent a tire/wheel assembly tointercept and deflect matter being projected by the tire/wheel assemblyfrom an outer circumference of the tire/wheel assembly and along any ofa plurality of linear trajectory paths tangent to the outercircumference of the tire when the tire/wheel assembly is in rotationduring vehicle operation and to permit the passage of air flow throughthe mud flap during vehicle operation to prevent the generation ofelevated aerodynamic drag, the mud flap comprising: a height, a width,and a thickness, where in the mounted position the height extendsprimarily in a vertical direction, the width extending perpendicular tothe height, the thickness of the mud flap being defined by a front sideand a rear side of the mud flap, the front side facing the tire/wheelassembly and configured to engage the matter being projected by therotating tire/wheel assembly and the rear side forming an outlet for thepassage of air flow through the mud flap; a barrier section configuredto intercept and deflect matter projected from an outer circumference ofthe tire when rotating during vehicle operation, the barrier sectionincluding a plurality of horizontal louvers, each horizontal louverforming an elongate member having a length extending primarily in adirection of the mud flap width, where the plurality of horizontallouvers are spaced apart in the direction of the mud flap height in theform of an array, the spacing between adjacent to horizontal louverswithin the plurality of horizontal louvers increasing with increasingheight of the mud flap, where each horizontal louver has a width and athickness, the horizontal louver width extending perpendicular to thehorizontal louver thickness and being greater than the horizontal louverthickness, both the horizontal louver width and the horizontal louverthickness extending perpendicular to a horizontal louver length, where acenterline of the horizontal louver thickness extends longitudinally atan inclination angle relative to a direction of the mud flap thickness,such that a bottom of the horizontal louver partially faces downward andpartially faces the front side of the mud flap, where the plurality ofhorizontal louvers are configured to intercept and deflect matter of aminimum size traveling along any linear trajectory path from the outercircumference of the tire/wheel assembly towards the front side of themud flap.
 2. The mud flap of claim 1, where for the matter to beprojected from the tire/wheel assembly along a linear trajectory pathtowards the front face of the mud flap in the mounted position, adjacenthorizontal louvers for the plurality of horizontal louvers are arrangedsuch that a line tangent to the outer circumference of the tire/wheelassembly first intersects an exterior surface of a first horizontallouver of adjacent horizontal louvers without extending into the firsthorizontal louver thickness and thereafter intersects a longitudinalcenterline of a thickness of a second horizontal louver adjacent to andelevationally higher than the first horizontal louver, where in adirection perpendicular to the line, the line is located within 3.81 mm(0.15 inches) of a location where the line would intersect the secondhorizontal louver without extending the second horizontal louverthickness.
 3. The mud flap of claim 2, where the line intersects anexterior surface of the second horizontal louver.
 4. The mud flap ofclaim 2, where the line is spaced apart from the second horizontallouver.
 5. The mud flap of claim 2, where the line intersects the secondhorizontal louver.
 6. The mud flap of claim 1, where for each horizontallouver arranged positionally higher in elevation within the array, theinclination angle by which the centerline of the horizontal louverthickness is oriented relative to the mud flap thickness remainssubstantially constant with increasing height of the mud flap.
 7. Themud flap of claim 1, where for the plurality of horizontal louvers, theinclination angle by which the centerline of each horizontal louverthickness is oriented relative to the mud flap thickness decreases withincreasing elevational position along the height of the mud flap.
 8. Themud flap of claim 1, where the thickness of each horizontal louver issubstantially the same for each louver within the plurality of louvers.9. The mud flap of claim 8, where the thickness of each horizontallouver varies along the width of the horizontal louver.
 10. The mud flapof claim 1, where the mud flap thickness is defined by a pair ofparallel planes each forming one of the front and rear sides of the mudflap.
 11. The mud flap of claim 1, where the inclination angle rangesfrom 15 to 50 degrees.
 12. The mud flap of claim 1, where the increasein spacing between adjacent horizontal louvers increases at a higherrate with increasing height along the mud flap, such that the increasein spacing is non-linear.
 13. The mud flap of claim 12, where thespacing between adjacent horizontal louvers is determined by thefollowing equation:F=Y+X·tan φ±S·sec φ, where Y represents a distance corresponding to avertical component of a corresponding louver width, X represents adistance corresponding to a horizontal component of a correspondinglouver width, φ represents the angle by which linear trajectory path isoriented relative to a ground plane or to a horizontal plane, and Srepresenting a distance of spacing desired in a direction perpendicularto a corresponding linear trajectory path along which points ofintersection with exterior surfaces of adjacent horizontal louvers arearranged.
 14. The mud flap of claim 1, where the spacing betweenadjacent horizontal louvers within the plurality of horizontal louversranges from 0.1 to 0.5 inches.
 15. The mud flap of claim 1, where anaerodynamic section is arranged above the barrier section, theaerodynamic section including a plurality of elongate members, whereadjacent elongate members within the plurality of elongate members arespaced apart, where the spacing between adjacent elongate members in theaerodynamic section as measured in a direction normal to the directionof elongate member length of one of the adjacent elongate members isgreater on average than the spacing between adjacent horizontal membersin the barrier section as measured in a direction normal to thedirection of horizontal member length of one of the adjacent horizontalmembers.
 16. A method of using a mud flap on a vehicle having atire/wheel assembly comprising: providing a mud flap in a mountedposition on the vehicle adjacent to the tire/wheel assembly, the mudflap configured to intercept and deflect matter being projected by thetire/wheel assembly from an outer circumference of the tire/wheelassembly and along any of a plurality of linear trajectory paths tangentto the outer circumference of the tire when the tire/wheel assembly isin rotation during vehicle operation and to permit the passage of airflow through the mud flap during vehicle operation to prevent thegeneration of elevated aerodynamic drag, the mud flap being any mud flaprecited in claim 1.